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Background: Virtual reality combined with spherical treadmills is used across species for studying neural circuits underlying navigation.
New Method: We developed an optical flow-based method for tracking treadmil ball motion in real-time using a single high-resolution camera.
Results: Tracking accuracy and timing were determined using calibration data. Ball tracking was performed at 500 Hz and integrated with an open source game engine for virtual reality projection. The projection was updated at 120 Hz with a latency with respect to ball motion of 30 ± 8 ms.
Comparison: with Existing Method(s) Optical flow based tracking of treadmill motion is typically achieved using optical mice. The camera-based optical flow tracking system developed here is based on off-the-shelf components and offers control over the image acquisition and processing parameters. This results in flexibility with respect to tracking conditions – such as ball surface texture, lighting conditions, or ball size – as well as camera alignment and calibration.
Conclusions: A fast system for rotational ball motion tracking suitable for virtual reality animal behavior across different scales was developed and characterized.

HCI and CSCW research as well as practice has strongly indicated the value of integrating (end) users in software development processes. Such integration can help address actual needs and wants, to avoid undesirable developments and to strengthen the User Experience of a product. A user-focused approach to software development has some conceptual overlap with agile software development practices, such as quick and iterative (user) testing. However, out in the wild, organisations seem to have difficulties actually mapping user-centered development with agile processes for a variety of reasons ranging from organisational or hierarchical aspects up to financial issues. This problem seems specially prevalent in Small and Medium sized Enterprises (SMEs) where such constraints can be even tighter than in larger organisations. To help understand those problems and to identify possible solutions, we turned to three quite different German software SMEs, varying in size, market focus and organisational structure. By way of qualitative field studies, we were able to identify key roles and tools as well as methodological, organisational and analytical practices and challenges in integrating (end) users into agile software development.

Playing is something profoundly human, and the ability to play is tightly tied to the intelligence of human beings, to their capability of thinking foresightedly and strategically, of choosing a particularly profitable move among all possible moves, of anticipating possible response moves by their adversaries, and thus to their capability of maximizing their own profit. By playing a game we here mean, in general, an interaction under preassigned rules, amongst several players each interested in maximizing their gains and acting strategically to this end. Games are encountered everywhere, be it as a party game, a card game, a computer game, or a game of hazard, be it as an individual or team sport such as chess, foil fencing, soccer, or ice hockey, be it companies organizing their strategies in a market economy, or states and other global players deciding on their geopolitical strategies.

In this course, we will take a detailed look at various breeds of spatial navigation interfaces that allow for locomotion in digital 3D environments such as games, virtual environments or even the exploration of abstract data sets. We will closely look into the basics of navigation, unraveling the psychophysics (including wayfinding) and actual navigation (travel) aspects. The theoretical foundations form the basis for the practical skillset we will develop, by providing an in-depth discussion of navigation devices and techniques, and a step-by-step discussion of multiple real-world case studies. Doing so, we will cover the full range of navigation techniques from handheld to full-body, highly engaging and partly unconventional methods and tackle spatial navigation with hands-on-experience and tips for design and validation of novel interfaces. In particular, we will be looking at affordable setups and ways to “trick” out users to enable a realistic feeling of self-motion in the explored environments. As such, the course unites the theory and practice of spatial navigation, serving as entry point to understand and improve upon currently existing methods for the application domain at hand.

In this paper, we provide a participatory design study of a mobile health platform for older adults that provides an integrative perspective on health data collected from different devices and apps. We illustrate the diversity and complexity of older adults’ perspectives in the context of health and technology use, the challenges which follow on for the design of mobile health platforms that support active and healthy ageing (AHA) and our approach to addressing these challenges through a participatory design (PD) process. Interviews were conducted with older adults aged 65+ in a two-month study with the goal of understanding perspectives on health and technologies for AHA support. We identified challenges and derived design ideas for a mobile health platform called “My-AHA”. For researchers in this field, the structured documentation of our procedures and results, as well as the implications derived provide valuable insights for the design of mobile health platforms for older adults.

We describe here a pilot user study comparing five different locomotion interfaces for virtual reality (VR) locomotion. We compared a standard non-motion cueing interface, Joystick, with four leaning-based seated motion-cueing interfaces: NaviChair, MuvMan, Head-Directed and Swivel Chair. The aim of this mixed methods study was to investigate the usability and user experience of each interface, in order to better understand relevant factors and guide the design of future ground-based VR locomotion interfaces. We asked participants to give talk-aloud feedback and simultaneously recorded their responses while they were performing a search task in VR. Afterwards, participants completed an online questionnaire. Although the Joystick was rated as more comfortable and precise than the other interfaces, the leaning-based interfaces showed a trend to provide more enjoyment and a greater sense of self-motion. There were also potential issues of using velocity-control for rotations in leaning-based interfaces when using HMDs instead of stationary displays. Developers need to focus on improving the controllability and perceived safety of these seated motion cueing interfaces.

This paper presents the newly founded Institute of Visual Computing at the Bonn-Rhine-Sieg University of Applied Sciences in Sankt Augustin, Germany. The research focuses as well as an overview of current projects are going to be part of this presentation.

This work addresses the issue of finding an optimal flight zone for a side-by-side tracking and following Unmanned Aerial Vehicle(UAV) adhering to space-restricting factors brought upon by a dynamic Vector Field Extraction (VFE) algorithm. The VFE algorithm demands a relatively perpendicular field of view of the UAV to the tracked vehicle, thereby enforcing the space-restricting factors which are distance, angle and altitude. The objective of the UAV is to perform side-by-side tracking and following of a lightweight ground vehicle while acquiring high quality video of tufts attached to the side of the tracked vehicle. The recorded video is supplied to the VFE algorithm that produces the positions and deformations of the tufts over time as they interact with the surrounding air, resulting in an airflow model of the tracked vehicle. The present limitations of wind tunnel tests and computational fluid dynamics simulation suggest the use of a UAV for real world evaluation of the aerodynamic properties of the vehicle’s exterior. The novelty of the proposed approach is alluded to defining the specific flight zone restricting factors while adhering to the VFE algorithm, where as a result we were capable of formalizing a locally-static and a globally-dynamic geofence attached to the tracked vehicle and enclosing the UAV.

This contribution investigates the application of established pansharpening algorithms for the fusion of hyperspectral images from Raman microspectroscopy and panchromatic images from conventional brightfield microscopy. Seven different methods based on multiresolution analysis and component substitution were applied and evaluated through visual assessment and quantitative quality measures at full and reduced resolution. The results indicate that, among the considered concepts, multiresolution methods are the more promising approaches for a physically and chemically meaningful fusion of the considered modalities. Here, pansharpening based on high-pass filtering led to the best results.